1. Field of the Invention
The present invention relates to liquid sampling devices, and in particular, to a liquid sampling apparatus which may be used to obtain samples of contaminants appearing on the surface of well water and directly beneath the surface thereof.
2. Discussion of the Relevant Art
The art abounds with devices which are used to sample liquids to determine their density, amount of contamination, etc. Generally, these devices disclose a valve which is sealed by the weight of the liquid sample contained in the container. Typical of these devices is U.S. Pat. No. 2,447,861 issued to Junge, which discloses a ball type closure mechanism that seals an opening provided in the base thereof. The ball is released when the sampling device reaches the bottom of the container and the string from which the device is suspended is allowed to slacken. The ball falls into position by the weight of gravity and is held there by the weight of the liquid in the device as the device is raised out of the fluid from which the sample has been obtained. Another device is disclosed in U.S. Pat. No. 1,585,072 issued to Banks. The apparatus disclosed therein includes a bottom flat plate which cooperates with a packing material thereby providing a seal holding the oil sample within the chamber. The flat plate functions as a valve and is disposed proximate the bottom opening.
Another device which is used as a liquor tester is disclosed in U.S. Pat. No. 164,451 issued to Hellen. Here a flapper type of valve is utilized to retain a liquid sample within the housing. One edge of the flat flapper is hingedly affixed to a circumferentially disposed lip portion and is caused to move in a downwardly direction sealing the opening when the device is removed from the liquid being sampled.
Generally, these devices are complicated mechanisms and require one or more movements of a string or contact with the bottom surface of a container for operation. These devices are not suitable to obtain samples of contamination appearing on the surface of liquids. Moreover, as these devices enter the liquid from which a sample is to be obtained, they generally disturb the surface thereby providing erroneous results by not including the liquids that may be floating on the surface of which the sample is to be taken. Moreover, the relatively simple devices discussed above may easily be rendered ineffective by dirt, or other particles which may enter the opening of the valve preventing the proper seating of the valve closing mechanisms.